It is frequently necessary, particularly in automobile construction and more generally in mass-production construction industries, to have available means, if possible easy to dismount, for rapidly joining together two tubes or pipes.
This is the case, for example, in car assembly, when the various elements constituting a conduit conveying a fluid, either petrol or cooling liquid for an engine, are to be connected.
A duct element generally comprises a supple or even semi-rigid pipe, fitted on a coupling to which it is hermetically fixed by any appropriate means, for example by a clamp. If two duct elements are fitted on the same coupling and are fixed thereto by clamps, it is relatively long and expensive to make the connection; moreover, dismantling may require the destruction of at least one of the clamps.
On the other hand, it is known to be advantageous to automatize, as much as possible, the various steps of mounting complex assemblies such as vehicles. However, it is indispensable, in that case, particularly concerning the connection of the duct elements, to limit the operations to simple movements, for example of translation, and to avoid the necessity of a specific orientation about an axis, in particular the axis of a translation.
Patents FR-A-1 535 163 and 1 403 312 and U.S. application 2 360 732, in particular, already disclose dismountable devices for rapidly joining together two pipes or sections of tubing. They generally comprise a coupling presenting, at one end adapted to receive a tube, a bore whose diameter is substantially equal to the outer diameter of the tube. This bore is provided with at least one supple sealing means capable of coming into contact with one of the walls of the tube. On the other hand, between the inlet orifice of the bore and the sealing means, the coupling comprises a housing which receives, for stopping the tube, a retractable member which is locally immobilized therein in the axial direction.
Such connection devices present numerous advantages, and in particular the easy positioning or dismantling thereof. In addition, the coupling may present two or more bores each associated with a member for stopping a tube, two tubes thus being connected in the same manner in each bore of the coupling.
However, the requirements of modern techniques and in particular the conditions of seal imposed in the case of the fluids conveyed being under pressure and possibly at high temperature, in practice often prevent the use of the known devices described hereinbefore: this is due in particular to the fact that the supple sealing means present physical characteristics different from those of the coupling, thus provoking phenomena of differential expansion which are detrimental to maintaining the tightness of the connection.
The invention provides a simple solution to the difficulty which has just been demonstrated and, in addition, allows various reliable embodiments, each presenting its own advantages.